Support more CORS options

Currently, Chalice supports CORS options to inject some headers ([https://github.com/aws/chalice#tutorial-cors-support](https://github.com/aws/chalice#tutorial-cors-support)).

But there are two missing options which are available in the web console when you enable CORS through API Gateway service :

Gateway Responses
DEFAULT_4XX DEFAULT_5XX

If they are not enabled, the error like "Missing Authentication Token" is sent without CORS headers which is very annoying when you make a request from your react web application because you can't get the status error code on non-cors requests.

```
No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:8000' is therefore not allowed access. The response had HTTP status code 403.
```